Hi everyone,
On Mon, Sep 09, 2024 at 06:01:54PM GMT, Snehal Koukuntla wrote:
When we share memory through FF-A and the description of the buffers exceeds the size of the mapped buffer, the fragmentation API is used. The fragmentation API allows specifying chunks of descriptors in subsequent FF-A fragment calls and no upper limit has been established for this. The entire memory region transferred is identified by a handle which can be used to reclaim the transferred memory. To be able to reclaim the memory, the description of the buffers has to fit in the ffa_desc_buf. Add a bounds check on the FF-A sharing path to prevent the memory reclaim from failing.
Also do_ffa_mem_xfer() does not need __always_inline
Fixes: 634d90cf0ac65 ("KVM: arm64: Handle FFA_MEM_LEND calls from the host") Cc: stable@vger.kernel.org Reviewed-by: Sebastian Ene sebastianene@google.com Signed-off-by: Snehal Koukuntla snehalreddy@google.com
arch/arm64/kvm/hyp/nvhe/ffa.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-)
diff --git a/arch/arm64/kvm/hyp/nvhe/ffa.c b/arch/arm64/kvm/hyp/nvhe/ffa.c index e715c157c2c4..637425f63fd1 100644 --- a/arch/arm64/kvm/hyp/nvhe/ffa.c +++ b/arch/arm64/kvm/hyp/nvhe/ffa.c @@ -426,7 +426,7 @@ static void do_ffa_mem_frag_tx(struct arm_smccc_res *res, return; } -static __always_inline void do_ffa_mem_xfer(const u64 func_id, +static void do_ffa_mem_xfer(const u64 func_id,
I am seeing a compilation error because of this.
----- LOG START ----- $ clang --version clang version 18.1.8 Target: x86_64-pc-linux-gnu Thread model: posix InstalledDir: /usr/bin $ make LLVM=1 ARCH=arm64 defconfig $ make LLVM=1 ARCH=arm64 Image ... arch/arm64/kvm/hyp/nvhe/ffa.c:443:2: error: call to '__compiletime_assert_776' declared with 'error' attribute: BUILD_BUG_ON failed: func_id != FFA_FN64_MEM_SHARE && func_id != FFA_FN64_MEM_LEND 443 | BUILD_BUG_ON(func_id != FFA_FN64_MEM_SHARE && | ^ ./include/linux/build_bug.h:50:2: note: expanded from macro 'BUILD_BUG_ON' 50 | BUILD_BUG_ON_MSG(condition, "BUILD_BUG_ON failed: " #condition) | ^ ./include/linux/build_bug.h:39:37: note: expanded from macro 'BUILD_BUG_ON_MSG' 39 | #define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg) | ^ ././include/linux/compiler_types.h:510:2: note: expanded from macro 'compiletime_assert' 510 | _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__) | ^ ././include/linux/compiler_types.h:498:2: note: expanded from macro '_compiletime_assert' 498 | __compiletime_assert(condition, msg, prefix, suffix) | ^ ././include/linux/compiler_types.h:491:4: note: expanded from macro '__compiletime_assert' 491 | prefix ## suffix(); \ | ^ <scratch space>:66:1: note: expanded from here 66 | __compiletime_assert_776 | ^ 1 error generated. make[6]: *** [arch/arm64/kvm/hyp/nvhe/Makefile:46: arch/arm64/kvm/hyp/nvhe/ffa.nvhe.o] Error 1 make[5]: *** [scripts/Makefile.build:485: arch/arm64/kvm/hyp/nvhe] Error 2 make[4]: *** [scripts/Makefile.build:485: arch/arm64/kvm/hyp] Error 2 make[3]: *** [scripts/Makefile.build:485: arch/arm64/kvm] Error 2 make[3]: *** Waiting for unfinished jobs.... ----- LOG END -----
Is this expected? Because when I add back the __always_inline, or change the BUILD_BUG_ON to BUG_ON, it compiles successfully.
Thanks, Wei-Lin Chang
struct arm_smccc_res *res, struct kvm_cpu_context *ctxt){ @@ -461,6 +461,11 @@ static __always_inline void do_ffa_mem_xfer(const u64 func_id, goto out_unlock; }
- if (len > ffa_desc_buf.len) {
ret = FFA_RET_NO_MEMORY;goto out_unlock;- }
- buf = hyp_buffers.tx; memcpy(buf, host_buffers.tx, fraglen);
2.46.0.598.g6f2099f65c-goog